Curable composition for electrical and electronic components

Abstract

Actinic radiation curable composition suitable for use in coating electronic components and as a printing ink comprising as the essential components: (a) a prepolymer selected from the group consisting of monofunctional vinyl resins and multifunctional vinyl resins; (b) a monomer selected from the group consisting of monofunctional vinyl monomers and multifunctional vinyl monomers; (c) a photoinitiator; (d) a filler; and (e) at least one surface active agent having a molecular weight greater than about 227; wherein one of the surface active agent or the filler has a pH greater than or equal to 7 and the other of the surface active agent or the filler has a pH less than or equal to 7 such that dispersion of the filler in the composition is enhanced and relatively high loading of filler in the composition is obtainable.

What is claimed is: 
     
       1. Actinic radiation curable composition suitable for use in coating electronic components and as a printing ink comprising: (a) a prepolymer selected from the group consisting of monofunctional vinyl resins and multifunctional vinyl resins;   (b) a monomer selected from the group consisting of monofunctional vinyl monomers and multifunctional vinyl monomers;   (c) a photoinitiator;   (d) at least one filler; and   (e) at least one surface active agent having a molecular weight greater than about 227; wherein one of the surface active agent or the filler has an overall pH greater than or equal to 7 and the other of the surface active agent or the filler has an overall pH less than or equal to 7 whereby the overall pH of the surface active agent(s) is less than 7 when the overall pH of the filler(s) is greater than 7, such that dispersion of the filler in the composition is enhanced and wherein the volume % of filler is at least 60 based on the competition of a prepolymer, a monomer, a photoinitiator, a surface active and a filler.     
     
     
       2. Actinic radiation curable composition according to claim 1 wherein the prepolymer is an aromatic epoxy acrylate. 
     
     
       3. Actinic radiation curable composition according to claim 2 wherein the aromatic epoxy acrylate is a diacrylate ester of bisphenol A epoxy. 
     
     
       4. Actinic radiation curable composition according to claim 1 wherein the monomer is trimethylol propane triacrylate and or 1,6 hexanediol diacrylate. 
     
     
       5. Actinic radiation curable composition according to claim 1 wherein the monomer is dicyclopentenyl acrylate. 
     
     
       6. Actinic radiation curable composition according to claim 1 wherein the photoinitiator is selected from the group of 2 isopropyl-thioxanthone, 2-2 dimethoxy 2, phenylacetophenone, 2 hydroxy 2 methyl 1 phenyl propan-1-one. 
     
     
       7. Actinic radiation curable composition according to claim 1 wherein the filler is calcium metasilicate. 
     
     
       8. Aticnic radiation curable composition according to claim 1 wherein the composition contains two surface active agents. 
     
     
       9. Actinic radiation curable composition according to claim 8 wherein one surface active agent is an organic phosphate ester. 
     
     
       10. Actinic radiation curable composition according to claim 1 wherein the filler used has been precoated with a surface active agent. 
     
     
       11. Actinic radiation curable composition according to claim 10 wherein the precoated filler is calcium metasilicate and the surface active agent is a silane. 
     
     
       12. Actinic radiation curable composition according to claim 11 wherein the silane is methacryloxypropyltrimethoxysilane. 
     
     
       13. Actinic radiation curable composition according to claim 12 wherein the said at least one surface active agent comprises an organic phosphate acid ester. 
     
     
       14. Actinic radiation curable composition according to claim 13 wherein the organic phosphate acid ester is selected from the group of nonyl nonoxynol-7-phosphate, nonyl nonoxynol-10-phosphate, nonyl nonoxynol-15-phosphate, nonoxynol-9-phosphate, nonoxynol-4-phosphate, trideceth-6-phosphate, trideceth4-phosphate, trideceth-7-phosphate, polyoxyethylene lauryl ether phosphate, polyoxyethylene phenyl ether phosphate, isoamyl alcohol ethoxylated phosphate, polyoxyethylene butoxyethyl ether phosphate, polyoxyethylene hexyl ether phosphate. 
     
     
       15. Actinic radiation curable composition according to claim 1 wherein the said at least one surface active agent is selected from the group of fish oil, linoleic acid, oleic acid, palmitic acid, stearic acid, carboxylic acids, oleoyl acids and titanates. 
     
     
       16. Actinic radiation curable composition according to claim 1 wherein the composition further comprises a flame retardant component. 
     
     
       17. Actinic radiation curable composition according to claim 1 wherein the composition further comprises an inhibitor component. 
     
     
       18. Actinic radiation curable composition according to claim 1 wherein the composition further includes a thixotropic agent. 
     
     
       19. Actinic radiation curable composition according to claim 18 wherein the thixotropic agent is fumed silica. 
     
     
       20. An electric component coated with a composition according to the composition of claim 1. 
     
     
       21. Actinic radiation curable composition according to claim 1 wherein the monofunctional vinyl monomer is selected from the group of monofunctional alpha, beta unsaturated carboxy monomers and wherein the multifunctional vinyl monomers are selected from the group of multifunctional alpha, beta unsaturated carboxy monomers. 
     
     
       22. Actinic radiation curable composition according to claim 1 wherein the prepolymer is between about 0 and about 70% by weight, the monomer is between about 1 and about 70% by weight, the photoinitiator is between about 1 and about 15 % by weight, and the surface active agent is between about 0.5 and about 4% by weight of the composition. 
     
     
       23. Actinic radiation curable composition according to claim 1 wherein the prepolymer is between about 3 and about 20% by weight, the monomer is between about 2 and about 6by weight, and the surface active agent is between about 0.5 and about 4% by weight of the composition. 
     
     
       24. Improved composition capable of being UV cured and suitable for use as a printing ink comprising: (a) a prepolymer selected from the group consisting of monofunctional vinyl ester resins and multifunctional ester resins;   (b) a monomer selected from the group consisting of monofunctional vinyl ester monomers selected from the group consisting of acrylate and methacrylate monomers and multifunctional vinyl ester monomers selected from the group consisting of arylate and methacrylate monomers;   (c) a photoinitiator;   (d) at least one pigment; and   (e) at least one surface active agent having a molecular weight greater than about 227; wherein one of the surface active agent or the pigment has an overall pH greater than or equal to 7 and the other of the surface active agent or pigment has whereby the overall pH of the surface active agent(s) is less than 7 when the overall pH of the pigment(s) is greater than 7, an overall pH less than or equal to 7 and wherein the volume % of pigment is at least 60 based on the competition of a prepolymer, a monomer, a photoinitiator, a surface active and a pigment.